In the past, as an exhaust gas purification catalyst arranged in an exhaust passage of an internal combustion engine, there has been developed an electric heating catalyst (hereinafter referred to as an EHC) in which a catalyst is heated by means of a heat generation element which generates heat by electrical energization thereof.
In the EHC, an insulating support member which serves to support the heat generation element and to insulate electricity is arranged between the heat generation element which generates heat by electrical energization thereof, and a case in which the heat generation element is received. For example, in Patent Document 1, there is disclosed a technique in which in an EHC, a mat of an insulating material is arranged between a carrier which is electrically energized to generate heat and a case in which the carrier is received.
In addition, in Patent Document 2, there is also disclosed a construction in which a catalytic converter having an EHC and a plasma reactor are arranged in an exhaust passage of an internal combustion engine which is mounted on a hybrid vehicle. With the construction described in Patent Document 2, a voltage is supplied to the EHC and the plasma reactor through a high voltage supply system from a battery which functions as a power supply of a motor-generator.